The Spice Of Life: Antibody Cocktail Targets Deadly Foodborne Germs

Derived from freeze-dried egg yolk, the substance is nicknamed a spice because it can be sprinkled or sprayed onto meats, fruits and vegetables to complement existing sanitation protocols. The so-called spice does not alter the taste of food.

Food contamination is on the rise in this country and is increasingly seen as a possible means of bioterrorism. One of the pathogens cited by the World Health Organization as a possible agent of bioterrorism is Salmonella, which this spice could protect against, the researchers say.

Research on the compound, which appears promising in early animal tests, was described today at the 225th national meeting of the American Chemical Society, the world's largest scientific society.

"This spice represents a safe, easy and inexpensive way to enhance your protection against deadly germs that attack humans via food. One day, it will be found in everyone's spice cabinet," says Hoon Sunwoo, Ph.D., chief investigator in the study and a food chemist at the University of Alberta in Canada.

"This spice does not kill the germs, but prevents them from infecting your body," says Sunwoo. The antibody can remain active one to two hours after being ingested. "That buys precious time that can help keep you alive," he adds.

As with the flu vaccine, hens are injected with specific foodborne pathogens, such as E. Coli, Salmonella, Campylobacter, Staphyloccoccus and Listeria. The animals then develop antibodies, called IgY (immunoglobulin Y), to these pathogens as their immune system attempts to attack them. These antibodies tend to accumulate in large amounts in the egg yolk, which is then collected, processed and freeze-dried to form a natural, germ-fighting cocktail.

Unlike the flu vaccine, which contains inactive viruses, the antibodies found in the spice are nonliving and pose no risk of infection.

Germs normally target and bind to the intestine, causing infection. In the presence of the antibody cocktail, the germs bind to their corresponding antibodies. The antibody-germ complex is then eliminated as waste, preventing infection.

More tests are needed before the spice is ready for consumer use, the researcher says. If all goes well, human tests could begin within a year, says Sunwoo. Early tests show that the spice can remain active in a freeze-dried condition for up to two years.

The spice will be most useful when traditional sanitation safeguards (i.e. rinsing, refrigeration, and thorough cooking) are unavailable or unreliable, the researcher says. Possible uses: foods that are prepared outdoors or meals that are eaten away from home, especially at salad bars and food bars.

The spice could be helpful for travelers to foreign countries in which food-handling practices are suboptimal. It can even be added to beverages, including water and fruit juice, says Sunwoo.

At the industrial level, the spice can be dissolved in water and sprayed onto meat carcasses to complement other processing methods, such as irradiation, or applied to final packaging. Such extra-protection methods would be welcome news for an industry that has been recently plagued with record-high meat recalls, says Sunwoo.

Although summer is the peak season for food contamination, cases can occur throughout the year. Consumers are urged to continue practicing safe-food handling techniques to reduce their chances of developing foodborne illness. People most vulnerable to serious complications from foodborne illness include infants, the elderly, pregnant women and those with weakened immune systems.

Antibodies can be developed for virtually any foodborne germs, including viruses, the researcher says. One possible candidate is the norovirus, which has recently been linked to a rash of outbreaks of flu-like illnesses on cruise ships.

Funding for this study was provided by the Natural Sciences and Engineering Research Council of Canada (NSERC).